The only time Staff ask you for a physical address is so that they can send you something: a contest prize, a postcard or holiday card, whatever.

Anecdotes are not data. Keeping that it mind, I can say that my own experience is that I'bles is the only organization to whom I have provided contact information and for which I don't even have a suspicion that the information has been passed on to third parties.

Banks? Stores? HMOs? They'll sell you out in a heartbeat. So far, I'bles doesn't appear to roll that way.

One can never say truly anything is 100%; the absence of a complaint doesn't mean bad hasn't happened, or won't happen -- but past behaviour usually indicates future; and I've never heard of a problem -- they have my info...heck I get a postcard from time to time :D